This thing is attached to my live rock, I've had this piece of rock for a few months and my girlfriend and I just today noticed this thing can move in and out away from the piece of rock, it's never moved from the same spot, I think it might be a mussel of some kind maybe. Theres two little almost leg looking things that barely stick out the top. This was the best picture I have as of now and a video of it moving.

Any help with this thing would be great, and slightly impressive


http://www.youtube.com/watch?v=tyPfH2crnz8

looks like an oyster of some sort. I had one that looked very similar to that and it made it about a month or so in my tank.

Definitely a bivalve... spiny oyster maybe?

Oyster.

awesome! are there any special maintenance for oysters?

Well... they are filter feeders. You could feed some phytoplankton or some other similar food. Try to arrange the rock so that it gets some flow, but not too much. They're not photosynthetic, so they don't need to be in light or anything.

I've had one stay alive for about a year now. It's pretty small, but kinda neat to show people.

k thanks, who would have guessed, this is my smallest piece of rock and it came with 2 hitchhiker pistol shrimp, a crab, an oyster and 4 snails. Things keep popping out from this thing

That's pretty cool. I got a hitchhiker oyster and some corals.

umm, am i looking at the wrong thing??? why would there be a feather duster inside a bivalve?

i think i see what youre looking at, in the picture i can see it, i just checked it and i dont see any feather dusters. it's definitely weird, i can't find anything that even distantly resembles it